1. Field of the Invention
The present invention relates generally to speaker systems for radiating acoustic energy in to a cabin of a motor vehicle.
2. Description of the Related Art
In the speaker systems of the car stereo components, the loudspeakers or speaker systems are ordinarily mounted in various inner panel portions of the motor vehicle defining the cabin, such as the dashboard, doors, rear window shelves and so on.
As shown in FIG. 1, when a speaker system including a loudspeaker unit S and an enclosure box 12 is intended to mount at a corner of a cabin A above the rear window shelf of the motor vehicle, it is installed in the way of the following procedures. Firstly, the speaker system having an enclosure box 12 accommodating a loudspeaker unit S is put in place onto the rear window shelf located between a back portion of a rear seat 10 and a rear windshield 15. Screws 13 are usually used to secure the speaker system to the rear window shelf. The screws 13 are inserted from above the the speaker system through small bores provided in the bottom of the enclosure box 12. Sequentially, the screws 13 are screwed by means of screwdriver 14 to the rear window shelf 11 to which the speaker system is fixed.
However, in the case of a motor vehicle of such type as coupe, hardtop, fastback or the like which has a rear windshield inclining at an acute angle with respect to the rear window shelf, there is not any space between the rear wind shelf and the rear windshield sufficient for allowing a person to handle a tool for installing the speaker system such as a screwdriver.
The Applicant have therefore conceived such a speaker system as shown in FIG. 2, in which a loudspeaker having a magnetic circuit including a permanent magnet 19 and a back yoke 20. With the back yoke 20 is engaged one end of a screw rod 27, the other end of which is fixed onto the back face of the rear window shelf. However, in this case there is a possibility that the back yoke 20 is separated from the magnet 19 because the magnet 19 and the back yoke 20 are only adhered by an adhesive.